Lawn mowers utilize rapidly rotating blades for cutting vegetation or grass to an even height. The blades are enclosed in a housing, which forms a part of a cutting deck assembly of the lawn mower. The cutting deck assembly can be front-mounted, rear-mounted, or mid-mounted with respect to the main lawn mower body. Front-mounted mowers are usually preferred for improved stability, maneuverability, and mowing performance.
However, lawn mowers are at times unsuited for use on severe terrain, including hills, undulations, highly sloped regions, and other irregular areas. Lawn mowers with rigid and/or fixed cutting decks are unsuitable for mowing such terrain and may lead to scalping, skipping, and streaking of grass. The cutter blades in a fixed cutting deck are unable to conform to the terrain beneath them. Consequently, small bumps or upwardly sloping regions that pass underneath the fixed cutting deck may be scalped while depressions or downwardly sloping regions may be undercut or entirely missed.
Traditionally, the aforementioned disadvantages of fixed cutting deck mowers are addressed by segmenting the relatively wide fixed cutting deck into a plurality of narrower cutter bars within the deck. Each cutter bar may carry one or more rotary cutter blades. For example, U.S. Pat. No. 7,089,722 discloses a flexible mechanism that interconnects the separate cutter bars with each other, enabling individual cutter bars to follow more closely the terrain beneath them. However, in this solution, the individual cutter bars are not able to change their height and/or orientation independent of each other in order to follow the ground contour closely. This again leads to an uneven cut on rough or undulating terrain especially where the height of the ground varies across the breadth of the mower.
Various known solutions disclose articulating cutting decks for mowing undulating terrain. However, such lawn mowers have a fixed cutting width and are inconvenient for mowing lawns with obstructions and narrow passages. Some mowers have side cutting decks that can be raised vertically and then folded to a transport position to change the cutting width or to move through confined passageways. However, the side cutting decks are inactive in the raised position, which results in redundancy and reduced flexibility.
Other known solutions include triplex trim mowers. Triplex trim mowers display variable cutting width for negotiating variable terrain. For example, U.S. Pat. No. 6,351,929 teaches laterally offset side cutting decks in a proposed triplex system for mowing around obstacles. However, such offset systems offer limited flexibility because the cutting width remains constant. Further, U.S. Pat. No. 7,437,864 discloses triplex system with variable cutting widths requiring an elaborate mechanism as both the longitudinal and lateral distances between the multiple individual cutting decks have to be changed. Furthermore, such mowers offer limited flexibility over undulating terrain because of the absence of angle or height adjustment means for individual cutting decks.
Moreover, front-mounted cutting deck assemblies require regular servicing and maintenance for removing the vegetation accumulated during the cutting process, and for cleaning and sharpening of the cutter blades. However, the underside of the cutting deck assembly is inaccessible for servicing in the operational position. The additional length of the lawn mower due to the front-mounted cutting deck assembly also poses a problem during storage in confined spaces. To solve the aforementioned problems, a tilting cutting deck assembly is usually provided for better access to the underside and for taking up less space during storage.
Various tilting deck systems have been proposed. In some proposed tilting deck systems, the cutting deck assembly needs to be manually disconnected from the main lawn mower body before it can be raised to an upright position. This results in a time consuming and tedious process for the operator. In related art, the cutting deck assembly is usually raised using an elaborate linkage mechanism, which results in an anti-clockwise rotation of the cutting deck. Since, the cutting deck in these solutions are not lifted to an upright position, auxiliary wheels are needed to support the cutting deck assembly during the tilting procedure and also in the raised position.
In available tilting deck systems, the components of the main lawn mower body such as the footplates and the steering wheel hinder the movement of the cutting deck to a completely upright position, thereby not resulting in a fully compact configuration.
Therefore, there is a need for an improved flexible cutting deck system for efficiently mowing rough terrain with obstacles and narrow passageways. Moreover, there is a need for an improved lawn mower system for providing a cutting deck position for easy serviceability and compactness for storage.